The main focus of this project is the development of a novel clinically applicable method to detect delivery of ISC-labeled anticancer drugs to solid tumors with noninvasive MR imaging. Preliminary data obtained with preclinical animal tumor models demonstrated feasibility of this technique using dedicated small animal MR scanners that operate at high magnetic fields (9.4 - 11T). Here we propose to translate the technology to clinical brain tumor studies using carbon-13 (13C) labeled anticancer agent, temozolomide, and state-of-theart Philips 3T MR clinical scanner. Initially, the method development will be performed on a head phantom and broadband channel will be optimized for inverse 13C detection with optional carbon-13 decoupling. Once the method is optimized, we will proceed to pilot clinical studies with brain tumor patients. Ten volunteer patients with malignant brain tumors that undergo treatment at the Sidney Kimmel Comprehensive Cancer Center of the Johns Hopkins University will participate in the study. Patients will receive 13C-labeled temozolomide orally and MRI scans will be performed at Philips 3T instrument. Briefly, novel HMQC-type pulse sequences for 2D/3D spectroscopic imaging will be implemented on the scanners. Dedicated 13C coils and appropriate RF filters for inverse 13C detection will be designed, manufactured, and tested for clinical experiments. All clinical studies involving patients will be performed in collaboration with Dr. Stuart Grossman.